Preparation method and application of a zirconium-based oxide adsorption material

Abstract

The present invention discloses a preparation method and application of a zirconium-based oxide adsorbent material, belonging to the technical field of adsorbent preparation. The preparation method comprises the following steps: using a mixed solution of zirconium oxychloride, cerium salt and iron salt as a precursor, obtaining a precipitate through a hydrothermal reaction under high pressure, and after centrifugation, washing and calcining the precipitate to prepare the zirconium-based oxide adsorbent material; wherein, the molar ratio of the zirconium oxychloride, cerium salt and iron salt is 100∶(3-6)∶(8-12). The present invention is prepared by using a certain proportion of zirconium oxychloride, cerium salt and iron salt as a precursor through a hydrothermal reaction and coprecipitation method. It not only has a simple preparation process and is convenient for large-scale production, but also the prepared zirconium-based oxide adsorbent material has excellent adsorption effects on fluorine, selenium, arsenic and heavy metals, which is of great significance for improving water pollution.

Description

Technical Field

[0001] The present invention belongs to the field of adsorbent preparation, and particularly relates to a preparation method and application of a zirconium-based oxide adsorbent material. Background Art

[0002] The adsorption method uses the porous structure of materials to physically adsorb pollution sources in polluted water. Due to its low cost, simple preparation process, and reusability, it is an important technology for removing groundwater pollution. Among them, the mainstream adsorption and filtration material is TiO2. The TiO2 material shows excellent adsorption effects on pollutants such as arsenic, but the removal rate of fluorine is not good. For example, Chinese Patent (CN107746073A) discloses a preparation method of granular titanium dioxide and lanthanum-loaded granular titanium dioxide. It uses titanyl sulfate as the precursor of titanium dioxide, adds lanthanum nitrate during the hydrolysis of titanyl sulfate, and prepares granular titanium dioxide and lanthanum-loaded granular titanium dioxide through co-hydrolysis and extrusion spheronization methods. Microcrystalline cellulose and hydroxypropyl methylcellulose are added during the preparation process to form the particles, and the strength is increased by extrusion with a granulator. Finally, a granular titanium dioxide material with high adsorption activity and mechanical strength and a lanthanum-loaded granular titanium dioxide composite material are prepared. However, even after lanthanum modification, its maximum adsorption capacity for fluorine is only 7.2 mgF / g. Summary of the Invention

[0003] To solve the above technical problems, the present invention proposes a preparation method and application of a zirconium-based oxide adsorbent material, which is prepared by hydrothermal reaction and co-precipitation using zirconyl chloride, cerium salt, and iron salt in a certain proportion as precursors. Not only is the preparation process simple and convenient for large-scale production, but also the prepared zirconium-based composite oxide adsorbent material has excellent adsorption effects on fluorine, selenium, arsenic, and heavy metals, which is of great significance for improving water pollution.

[0004] The purpose of the first aspect of the present invention is to provide a preparation method of a zirconium-based oxide adsorbent material, including the following steps: using a mixed solution of zirconyl chloride, cerium salt, and iron salt as a precursor, obtaining a precipitate through high-pressure hydrothermal reaction, and preparing the zirconium-based oxide adsorbent material after centrifuging, washing, and calcining the precipitate; wherein, the molar ratio of zirconyl chloride, cerium salt, and iron salt is 100∶(3 - 6)∶(8 - 12).

[0005] The present invention obtains a composite adsorbent through process steps such as high-pressure hydrothermal reaction, coprecipitation, and calcination of a precursor solution. This adsorbent uses zirconia as the matrix and loads a certain amount of nanoscale cerium oxide and iron oxide, and has excellent specific surface area and adsorption activity. Among them, zirconia has a high specific surface area and a special stacking structure, and the oxygen-containing functional groups can provide a large number of adsorption sites, thus effectively adsorbing pollutant ions. The surface-loaded nano cerium oxide and iron oxide play a synergistic promoting role in the adsorption. In addition, zirconia has stable chemical properties and has a high selectivity for fluoride ions, which makes it perform excellently in removing fluoride pollution in water.

[0006] Further preferably, the molar ratio of zirconium oxychloride, cerium salt, and iron salt is 100∶(5 - 6)∶(9 - 10).

[0007] Preferably, the cerium salt includes but is not limited to cerous nitrate, cerium nitrate, cerium sulfate, or cerium chloride; among them, since the solubility of cerium nitrate and cerium sulfate is greater than that of cerium chloride, therefore, the cerium salt is preferably cerium nitrate or cerium sulfate.

[0008] Preferably, the iron salt includes but is not limited to ferric chloride, ferric sulfate, or ferric nitrate.

[0009] Preferably, zirconium oxychloride is added in the form of ZrOCl2·8H2O, and the dosage ratio of ZrOCl2·8H2O to solvent water is (1 - 5) g∶(10 - 50) mL.

[0010] More preferably, the dosage ratio of ZrOCl2·8H2O to solvent water is 1.5 g∶20 mL.

[0011] In a preferred embodiment, the conditions of the high-pressure hydrothermal reaction are: temperature 180 - 210 °C, time 8 - 12 h, and heating rate 10 - 30 °C / min.

[0012] Further preferably, through experimental verification, the optimal hydrothermal temperature is 200 °C, the optimal heating rate is 30 °C / min, and the time of the hydrothermal reaction is 10 h; therefore, the conditions of the high-pressure hydrothermal reaction are preferably: temperature 200 °C, time 10 h, and heating rate 30 °C / min.

[0013] Preferably, the conditions of the calcination are: first drying at 60 - 80 °C for 6 - 10 h, and then calcining at 260 - 350 °C for 3 - 6 h.

[0014] Preferably, the calcination temperature is 300 °C and the calcination time is 4 h.

[0015] Preferably, the atmosphere of the calcination is an air atmosphere.

[0016] The purpose of the second aspect of the present invention is to provide a zirconium-based oxide adsorption material prepared by the above preparation method.

[0017] The purpose of the third aspect of the present invention is to provide the use of the above zirconium-based oxide adsorption material in adsorbing and removing heavy metals, selenium, arsenic or fluorine pollution in groundwater, surface water or industrial wastewater.

[0018] Preferably, the heavy metal is cadmium.

[0019] The present invention has at least the following technical effects:

[0020] The zirconium-based oxide adsorption material described in the present invention can efficiently remove arsenic, fluorine pollutants in drinking water and heavy metal pollutants such as selenium and chromium brought by industrial pollution. Description of the Drawings

[0021] The drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0022] Figure 1 is the scanning electron microscope image (SEM) of the zirconium-based oxide adsorption material prepared in Example 1.

[0023] Figure 2 is the XPS diagram of the zirconium-based oxide adsorption material prepared in Comparative Example 1.

[0024] Figure 3 is the XRD diagram of the zirconium-based oxide adsorption material prepared in Comparative Example 1.

[0025] Figure 4 is the N2 adsorption-desorption curve of the zirconium-based oxide adsorption material prepared in Example 1.

[0026] Figure 5 is the removal efficiency of arsenic, fluorine, selenium, and chromium by the zirconium-based oxide adsorption material prepared in Example 1.

[0027] Figure 6 Adsorption isotherms and Langmuir fitting results of arsenic, fluorine, and selenium by the zirconium-based oxide adsorption material prepared in Example 1. Detailed Embodiments

[0028] Implementable methods discovered in this field. Groundwater pollution includes heavy metal pollution, as well as pollution by fluorine, selenium, arsenic, etc. Taking fluorine pollution as an example, fluorine is an industrial heavy metal widely used in the production of fluorination reagents and fluxes in metal smelting. It is located in Group VIIA of the second period of the periodic table, with an atomic number of 9 and a relative atomic mass of 19.00. Most fluorine in nature is in a combined state, mainly including: fluorite (CaF2), fluorapatite [Ca5(PO4)3F], cryolite (Na3AlF6), etc. They are all important chemical raw materials and are widely used in industrial production such as aluminum smelting, phosphate fertilizer, steel, and organic fluorine high-grade lubricants, oxygen difluoride in rocket propellants, hydrazine fluoride, etc. Fluorine-containing wastewater from industries such as electroplating and metal processing, as well as washing water for treating fluorine-containing waste gas by the washing method, will cause pollution to water bodies and soil after being discharged into the environment. The settlement of fluorine-containing soot or being washed by precipitation will pollute the soil and groundwater. Fluorine in the human body directly comes from drinking water, food, and air. Fluorine is one of the essential trace elements for the human body. Trace amounts of fluorine can promote the growth and development of children and prevent dental caries. The daily intake of fluoride by adults is generally 1.0 - 1.5 mg, and excessive intake will endanger health. There are more than 20 forms of fluorine in groundwater, and they change with the properties and chemical composition of the water medium, and the proportional relationship of their occurrence forms is also adjusted accordingly. In shallow groundwater with a neutral or slightly alkaline (pH = 7 - 8) environment, there are only 10 forms of fluorine components, namely F, BF(OH)3 - 、HFaq、CaF + 、MgF + 、MnF + 、AlF2 + 、AlF2 + 、AlF3 and AlF4 - ,among which F, MgF + 、CaF + are the main forms. Generally, F accounts for 79% - 96% of TF (total fluorine concentration), followed by MgF and CaF, accounting for 3.1% - 19.2% and 0.3% - 3.0% of TF respectively. The groundwater chemical environment varies from place to place. If it contains CO3 2- 、PO4 3- 、organic matter and other substances, it will affect the fluorine removal effect. Therefore, it is very important to select a fluorine removal method suitable for local conditions. Fluorine is one of the essential trace elements for human life activities. It is a normal component of bones and teeth and is necessary for the formation of enamel, and has a protective effect on osteoporosis. However, like other elements, both excessive and insufficient fluorine are harmful to human health. Excessive fluorine will cause fluorosis, manifested as a systemic chronic damage mainly involving teeth and bones.

[0029] Implementable methods discovered in this field. Therefore, purification technology for groundwater is crucial for drinking water safety. Currently, the main groundwater treatment technologies at home and abroad are as follows:

[0030] 1. Pump and Treat (P&T) technology, the earliest groundwater pollution remediation technology and a representative technology for off-site groundwater remediation. Since groundwater pollution remediation began in the 1980s, P&T technology has remained the main method for groundwater pollution treatment. Traditional P&T technology involves pumping out contaminated groundwater and treating it on the ground. In recent years, with the continuous in-depth research on pollution treatment, this technology has a broader meaning. Any technology that involves pumping or injecting groundwater during the groundwater pollution treatment process is classified as P&T technology.

[0031] 2. Monitored Natural Attenuation (MNA) technology emerged relatively late and was formally used for groundwater pollution treatment in the 1990s. This technology is based on the physical and chemical conditions of the polluted site and the natural attenuation ability of pollutants to carry out pollution remediation, thereby achieving the goals of reducing pollutant concentration, toxicity, and mobility. In addition, MNA technology must also adopt corresponding monitoring and control technologies according to the treatment goals of the polluted area to monitor and evaluate the natural remediation process of groundwater.

[0032] 3. In-situ remediation technology. In recent years, the rise of groundwater in-situ remediation technology has received extensive attention. Typical groundwater in-situ remediation technologies include: Air Sparging (AS) technology, Permeable Reactive Barrier (PRB) technology, in-situ bioremediation technology, Multi-Phase Extraction technology, in-situ chemical treatment technology, phytoremediation technology, and remediation technologies that combine multiple methods.

[0033] 4. Hydrodynamic control method: Establish a well group control system. By artificially pumping groundwater or injecting water into the aquifer, the original hydraulic gradient of groundwater is changed, and then the contaminated groundwater body is separated from the uncontaminated clean water body. It can be divided into the upstream watershed method and the downstream watershed method according to the specific hydrogeological conditions of the local area. The equipment for this method is simple and the operation cost is low. It has a good effect on preventing the spread of pollutants in the initial stage of pollution and high repair efficiency, but it is generally used as a temporary control method.

[0034] 5. Physical Barrier Method: By injecting grout underground, a curtain is formed around the contaminated water body to enclose the contaminated water body and prevent the further spread of pollutants. Such as slurry cut-off walls, vibro-pile cut-off walls, sheet pile cut-off walls, block replacement, membrane and synthetic material curtain enclosure methods, etc. The principle is similar to that of the grout curtain method, which is to establish a physical barrier underground to isolate the contaminated water body.

[0035] 6. Passive Collection Method: Dig a trench deep enough downstream of the groundwater flow, arrange a collection system to collect the pollutants floating on the water surface (such as oil pollutants), or collect all the contaminated groundwater for treatment. This method is more effective in treating light pollutants.

[0036] 5. There are also some other technologies, such as in-situ solidification / stabilization technology: By adding solidifying / stabilizing agents to the contaminated medium, physical and chemical reactions occur between them and the pollutants, sealing the contaminated soil into a solidified body with a complete structure and a low permeability coefficient, or transforming the pollutants into chemically inactive forms.

[0037] Chemical Oxidation / Reduction Technology: Inject oxidants or reductants into the contaminated area of soil or groundwater, and through oxidation or reduction, transform the pollutants into non-toxic or relatively less toxic substances.

[0038] Thermal Desorption Technology: Heat the contaminated soil directly or indirectly to above the boiling point of the target pollutants, so that the pollutants vaporize and volatilize and separate from the soil particles.

[0039] Soil Elution Technology: Use physical separation or enhanced elution and other means to separate the heavy contaminated soil components or transfer the pollutants from the soil phase to the liquid phase.

[0040] Cement Kiln Co-disposal Technology: Utilize the high temperature and long gas residence time in the cement rotary kiln to incinerate and solidify the contaminated soil.

[0041] Phytoremediation Technology: Use plants to remove, transform and destroy the pollutants in the soil through extraction, rhizofiltration, volatilization and immobilization and other methods.

[0042] Barrier Landfill Technology: Place the contaminated soil in an impermeable barrier landfill or block the migration and diffusion path of pollutants by laying a barrier layer.

[0043] Natural Attenuation Technology: Rely on the physical, chemical and biological actions occurring naturally at the site to reduce the quantity, toxicity and mobility of pollutants in groundwater and soil to an acceptable risk level.

[0044] Multi-phase Extraction Technology: Extract soil gas, groundwater, floating oil, etc. from the underground contaminated area to the ground through vacuum extraction for phase separation and treatment.

[0045] Soil vapor extraction technology: Supply air or oxygen to the soil, rely on the aerobic activities of microorganisms to promote the degradation of pollutants, and at the same time use the pressure gradient in the soil to cause volatile organic compounds and degradation products to flow towards the extraction wells and be extracted and removed.

[0046] As an implementable method discovered in this field. At present, there are many preparation processes for zirconium-based oxides as adsorbents, but the specific surface areas of zirconium-based oxides prepared in the prior art all need to be improved. For example, a kind of nanoporous zirconium oxide adsorbent prepared by Taiyuan University of Science and Technology uses an organic zirconium source as a precursor, dodecanedioic acid, a long-chain aliphatic dicarboxylic acid, as a dispersant, cetyltrimethylammonium bromide as a cationic template agent, and an ethanol aqueous solution as a reaction system. Under weak acid conditions, a solvent evaporation self-assembly reaction is carried out to form a zirconium-containing wet gel, and then a zirconium oxide adsorbent material is prepared by high-temperature calcination. The specific surface area of the zirconium-based oxide adsorbent prepared by this process is 90.2 - 106.3 m 2 / g.

[0047] As an implementable method discovered in this field. Another example is a zirconium oxide spherical adsorbent and its preparation method and application disclosed by China National Petroleum Corporation. Add an organic ammonium salt and an organic zirconium precursor to a mixed solution of glacial acetic acid and formic acid, then add water thereto, transfer the above mixed solution to a closed reaction kettle, and carry out a constant-temperature reaction at 160°C - 220°C for 12 - 48 hours, cool, separate and take the solid product, wash and dry it, and then calcine. The zirconium oxide spherical adsorbent prepared by the present invention has a diameter of 200 - 400 nm and mesopores with a diameter of 1 - 10 nm are distributed inside. The spherical adsorbent is a sphere formed by self-assembly of zirconium oxide nanocrystals with a unit size of 5 - 10 nm; the specific surface area of the adsorbent prepared by this process is 100 - 250 m 2 / g.

[0048] As an implementable method discovered in the art. There are also some zirconium-based oxides doped with other elements. For example, a zirconium-based nitrogen oxide adsorbent is a composite oxide with zirconia as the main component and containing two modifying elements, silver and manganese. Among them, the molar percentages of silver and manganese are: silver is 2 - 10%, manganese is 5 - 50%, and the balance is zirconia; the composite oxide is a tetragonal crystal composite oxide with a specific surface area of 80 - 250 m2 / g prepared by the impregnation method, precipitation method or microemulsion method. The adsorbent material of this technology can be prepared by any known method. Among them, a better method is: the adsorbent containing manganese and zirconium can be prepared by the co-precipitation method or microemulsion method; the adsorbent containing silver, manganese and zirconium can be obtained by the equal-volume impregnation method by impregnating the adsorbent material containing manganese and zirconium prepared above with a silver nitrate solution; the adsorbent containing silver, manganese and zirconium can also be prepared by the co-precipitation method or microemulsion method. The evaluation of the adsorption performance of nitrogen oxides is carried out according to the following steps: placing the above solid adsorbent in a flowing thermogravimetric analyzer, the concentration of nitrogen oxides in the gas stream is several to 5000 ppm, the oxygen concentration is 0 - 20%, and the remaining balance gas is nitrogen; using thermogravimetric analysis to detect the change value of the weight gain of the adsorbent with time at a specified temperature to obtain the adsorption curve of the adsorbent; when the weight gain does not change significantly with time, that is, saturated adsorption is reached. At this time, the obtained weight gain is recorded as the equilibrium adsorption capacity, which is expressed by the mass of nitrogen oxides adsorbed per gram of adsorbent; the time for the adsorbent of the present invention to reach the equilibrium adsorption capacity is generally within 10 - 120 minutes; after the adsorbent of the present invention reaches saturated adsorption, it can be heated to 250 - 600 °C in an inert atmosphere or reducing atmosphere to release the adsorbed nitrogen oxides or react and convert them into nitrogen for further use. From the weight loss curve of the thermogravimetric analyzer, the desorption amount of the gas can be detected and the complete desorption temperature can be determined. In an actual waste gas environment, such as flue gas or the exhaust gas of an internal combustion engine, water vapor often coexists with nitrogen oxides. Therefore, in the present invention, by the method of simultaneously introducing water and nitrogen oxides into the carrier gas, the experiment of nitrogen oxide adsorption by the adsorbent material in water vapor was investigated. The volume content of water vapor in the experiment process is 1 - 10%. This type of material has good anti-water competitive adsorption ability. The characteristics of the present invention: The adsorbent does not contain platinum group precious metals, is a composite oxide containing zirconium, manganese and silver, etc., and is a high specific surface area adsorbent material with a specific surface area of 80 - 250 m 2 / g.

[0049] As an implementable method discovered in the art. A preparation method of a high-strength pectin zirconium hydroxide microsphere adsorbent comprises the following steps: 1) Mix zirconium hydroxide powder, diammonium hydrogen carbonate, and polyethylene glycol, and add deionized water, and ultrasonically make the mixture form a uniformly dispersed suspension; 2) Add deionized water to pectin and stir until the pectin is completely dissolved; 3) Add the suspension obtained in step 1) to the pectin solution in step 2), and stir evenly at 80-95 °C to obtain a white gel liquid; 4) Drop the white gel liquid obtained in step 3) into dimethyl silicone oil through a dropper, filter and wash the white particles below the dimethyl silicone oil, and vacuum dry to obtain the pectin zirconium hydroxide microsphere adsorbent. Improvement: The mass ratio of the zirconium hydroxide powder, diammonium hydrogen carbonate, polyethylene glycol, and pectin is 100:1-5:0.1-0.5:10-30. In step 2), when adding deionized water to pectin, stir at 25-45 °C for 2-3 h until dissolved. As a further improvement of the technical solution of the preparation method of the present invention, in step 4), the particle size of the obtained pectin zirconium hydroxide microsphere adsorbent is 0.6-1.2 mm. In step 4), the conditions for vacuum drying are vacuum drying at 60-80 °C for 6-10 h. The diammonium hydrogen carbonate can be replaced with ammonium bicarbonate or ammonium carbonate. The molecular weight of the polyethylene glycol is 2000-6000.

[0050] However, the specific surface area of the adsorbent material prepared by the above technology still needs to be improved. To further improve the specific surface area of the adsorbent and enhance the adsorption effect, the embodiment of the present invention discloses a preparation method of a zirconium-based oxide adsorbent, which comprises the following steps:

[0051] 1) Dissolution: Dissolve 1-5 g of ZrOCl2·8H2O in 10-50 mL of ultrapure water at a stirring speed of 100-300 r / min, and then add Ce(NO3)3·6H2O and Fe(NO3)3 according to the molar ratio of Zr∶Ce∶Fe of 100∶(3-6)∶(8-12) to obtain a composite zirconium salt precursor solution;

[0052] 2) High-pressure reaction: Transfer the above composite zirconium salt precursor solution into a high-pressure reaction kettle, and place the high-pressure reaction kettle in an oven and heat it to 160-220 °C at a speed of 10-40 °C / min, and maintain for 8-12 h;

[0053] 3) Cleaning: After naturally cooling to room temperature, centrifuge to remove the supernatant to obtain a precipitate, and rinse the precipitate with ultrapure water 2-5 times;

[0054] 4) Calcination: Dry the precipitate at 60-80 °C for 5-10 h, and then calcine it at 240-350 °C in an air atmosphere for 3-6 h to obtain a zirconium-based oxide adsorbent.

[0055] In a preferred embodiment, the optimal dosage ratio of the composite zirconium salt precursor solution in step 1) is 1-2 g of ZrOCl2·8H2O added to 10-25 mL of ultrapure water.

[0056] The reaction carried out in the autoclave is a hydrothermal reaction. The purpose of the hydrothermal reaction is to enable the adsorption material to undergo a reduction reaction while obtaining a product with a nanoscale particle size, so as to increase its specific surface area and provide favorable conditions for adsorbing pollutant source ions. In a preferred embodiment, the optimal high-pressure reaction conditions in step 2) are to heat up to 200 °C at a rate of 30 °C / min and maintain for 10 h.

[0057] In a preferred embodiment, the purity of the precipitate after centrifugation in step 3) can meet the requirements after being washed 3 times with ultrapure water.

[0058] The purpose of drying is to remove moisture and avoid adverse effects of moisture on the morphology of the adsorbent during the subsequent high-temperature calcination process. Therefore, the temperature during the drying process should not be too high or too low. If the temperature is too high, it will cause partial oxidation, and if the temperature is too low, the moisture removal will be too slow or incomplete. In a preferred embodiment, the optimal drying conditions in step 4) are 60-65 °C for 6-8 h. As an example, the drying condition is drying at 60 °C for 8 h.

[0059] The purpose of calcination is to obtain metal oxides. In a preferred embodiment, the optimal calcination conditions in step 4) are in an air atmosphere, heating up to 300 °C at a rate of 30 °C / min and calcining for 4-5 h.

[0060] Now, various exemplary embodiments of the present invention will be described in detail. This detailed description should not be considered as a limitation of the present invention, but should be understood as a more detailed description of certain aspects, characteristics, and implementation schemes of the present invention.

[0061] It should be understood that the terms described in the present invention are only for describing specific embodiments and are not used to limit the present invention. Additionally, for the numerical ranges in the present invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each intermediate value within any stated value or stated range, as well as each smaller range between any other stated value or intermediate value within the stated range, is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded from the range.

[0062] Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Although this invention only describes preferred methods and materials, any methods and materials similar or equivalent to those described herein can also be used in the implementation or testing of this invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials related to the said documents. In case of conflict with any incorporated document, the content of this specification shall prevail.

[0063] Without departing from the scope or spirit of this invention, various improvements and changes can be made to the specific embodiments of the specification of this invention, which are obvious to those skilled in the art. Other embodiments obtained from the specification of this invention are obvious to those skilled in the art. The specification and examples of this invention are merely exemplary.

[0064] Regarding the use of "comprising", "including", "having", "containing", etc. in this article, they are all open-ended terms, meaning including but not limited to.

[0065] The raw materials in the embodiments of this invention are all obtained through commercial purchase.

[0066] Example 1

[0067] A zirconium-based oxide adsorption material is prepared as follows:

[0068] Under magnetic stirring, 1.5 g of ZrOCl₂·8H₂O solid is dissolved in 20 mL of ultrapure water. Ce(NO₃)₃·6H₂O and Fe(NO₃)₃ are added according to the molar ratio of Zr∶Ce∶Fe of 100∶3∶12. Subsequently, it is transferred to a 50 mL high-pressure reactor and heated to 200 °C at a heating rate of 30 °C / min. It is maintained at 200 °C for 10 h. After natural cooling, the solid and liquid are separated by centrifugation. The solid is washed 3 times with ultrapure water, dried in an oven at 60 °C for 8 h, and finally calcined in a muffle furnace at 300 °C for 4 h (in an air atmosphere). After natural cooling, the zirconium-based oxide adsorption material is obtained.

[0069] The scanning electron microscope image of the zirconium-based oxide adsorption material is shown in Figure 1 , from Figure 1 it can be seen that the zirconium-based oxide adsorption material prepared in this example is nanoscale particles with a rough surface.

[0070] Figure 4 is the N₂ adsorption-desorption curve of the zirconium-based oxide adsorption material prepared in this example. From Figure 4 it can be seen that the specific surface area of the zirconium-based oxide adsorption material prepared in this example is as high as 385 m 2 / g, with a pore size of approximately 9.8 nm. This relatively large specific surface area provides favorable conditions for its full play of adsorption performance.

[0071] Example 2

[0072] A zirconium-based oxide adsorption material is prepared as follows:

[0073] Under magnetic stirring, 1.5 g of ZrOCl2·8H2O solid is dissolved in 20 mL of ultrapure water. Ce(NO3)3·6H2O and Fe(NO3)3 are added according to the molar ratio of Zr∶Ce∶Fe of 100∶5∶12. Subsequently, it is transferred to a 50 mL high-pressure reactor and heated to 200 °C at a heating rate of 30 °C / min. It is maintained at 200 °C for 10 h. After natural cooling, the solid and liquid are centrifuged and separated. The solid is washed 3 times with ultrapure water, dried in an oven at 60 °C for 8 h, and finally calcined in a muffle furnace at 300 °C for 4 h (in an air atmosphere). After natural cooling, the zirconium-based oxide adsorption material is obtained.

[0074] Example 3

[0075] A zirconium-based oxide adsorption material is prepared as follows:

[0076] Under magnetic stirring, 1.5 g of ZrOCl2·8H2O solid is dissolved in 20 mL of ultrapure water. CeN3O9·6H2O and Fe(NO3)3 are added according to the molar ratio of Zr∶Ce∶Fe of 100∶6∶12. Subsequently, it is transferred to a 50 mL high-pressure reactor and heated to 200 °C at a heating rate of 30 °C / min. It is maintained at 200 °C for 10 h. After natural cooling, the solid and liquid are centrifuged and separated. The solid is washed 3 times with ultrapure water, dried in an oven at 60 °C for 8 h, and finally calcined in a muffle furnace at 300 °C for 4 h (in an air atmosphere). After natural cooling, the zirconium-based oxide adsorption material is obtained.

[0077] Example 4

[0078] A zirconium-based oxide adsorption material is prepared as follows:

[0079] Under magnetic stirring, 1.5 g of ZrOCl2·8H2O solid is dissolved in 20 mL of ultrapure water. Ce(NO3)3·6H2O and Fe(NO3)3 are added according to the molar ratio of Zr∶Ce∶Fe of 100∶5∶8. Subsequently, it is transferred to a 50 mL high-pressure reactor and heated to 200 °C at a heating rate of 30 °C / min. It is maintained at 200 °C for 10 h. After natural cooling, the solid and liquid are centrifuged and separated. The solid is washed 3 times with ultrapure water, dried in an oven at 60 °C for 8 h, and finally calcined in a muffle furnace at 300 °C for 4 h (in an air atmosphere). After natural cooling, the zirconium-based oxide adsorption material is obtained.

[0080] Example 5

[0081] A zirconium-based oxide adsorption material, the preparation method is as follows:

[0082] Under magnetic stirring, 1.5 g of ZrOCl2·8H2O solid was dissolved in 20 mL of ultrapure water, and Ce(NO3)3·6H2O and Fe(NO3)3 were added according to the molar ratio of Zr∶Ce∶Fe of 100∶5∶10. Subsequently, it was transferred to a 50 mL high-pressure reactor, heated to 200 °C at a heating rate of 30 °C / min, maintained at 200 °C for 10 h. After natural cooling, the solid and liquid were centrifuged and separated, the solid was washed 3 times with ultrapure water, the solid was dried in an oven at 60 °C for 8 h, and finally calcined in a muffle furnace at 300 °C for 4 h (air atmosphere), and the zirconium-based oxide adsorption material was obtained after natural cooling.

[0083] Example 6

[0084] A zirconium-based oxide adsorption material, the preparation method is as follows:

[0085] Under magnetic stirring, 1.5 g of ZrOCl2·8H2O solid was dissolved in 20 mL of ultrapure water, and Ce(NO3)3·6H2O and Fe(NO3)3 were added according to the molar ratio of Zr∶Ce∶Fe of 100∶5∶12. Subsequently, it was transferred to a 50 mL high-pressure reactor, heated to 200 °C at a heating rate of 30 °C / min, maintained at 200 °C for 10 h. After natural cooling, the solid and liquid were centrifuged and separated, the solid was washed 3 times with ultrapure water, the solid was dried in an oven at 60 °C for 8 h, and finally calcined in a muffle furnace at 260 °C for 6 h (air atmosphere), and the zirconium-based oxide adsorption material was obtained after natural cooling.

[0086] Example 7

[0087] A zirconium-based oxide adsorption material, the preparation method is as follows:

[0088] Under magnetic stirring, 1.5 g of ZrOCl2·8H2O solid was dissolved in 20 mL of ultrapure water, and Ce(NO3)3·6H2O and Fe(NO3)3 were added according to the molar ratio of Zr∶Ce∶Fe of 100∶5∶12. Subsequently, it was transferred to a 50 mL high-pressure reactor, heated to 200 °C at a heating rate of 30 °C / min, maintained at 200 °C for 10 h. After natural cooling, the solid and liquid were centrifuged and separated, the solid was washed 3 times with ultrapure water, the solid was dried in an oven at 60 °C for 8 h, and finally calcined in a muffle furnace at 350 °C for 3 h (air atmosphere), and the zirconium-based oxide adsorption material was obtained after natural cooling.

[0089] Comparative Example 1

[0090] A zirconium-based oxide adsorption material, the preparation method is as follows:

[0091] Under magnetic stirring, dissolve 1.5 g of ZrOCl2·8H2O solid in 20 mL of ultrapure water, add Ce(NO3)3·6H2O and Fe(NO3)3 according to the molar ratio of Zr∶Ce∶Fe of 100∶2∶13, then transfer to a 50 mL high-pressure reactor, heat up to 200 °C at a heating rate of 30 °C / min, maintain at 200 °C for 10 h, after natural cooling, centrifuge to separate the solid and liquid, wash the solid 3 times with ultrapure water, dry the solid in an oven at 60 °C for 8 h, and finally put it into a muffle furnace and calcine at 300 °C for 4 h (in air atmosphere), and obtain the zirconium-based oxide adsorption material after natural cooling.

[0092] Comparative Example 2

[0093] A zirconium-based oxide adsorption material, the preparation method is as follows:

[0094] Under magnetic stirring, dissolve 1.5 g of ZrOCl2·8H2O solid in 20 mL of ultrapure water, add Ce(NO3)3·6H2O and Fe(NO3)3 according to the molar ratio of Zr∶Ce∶Fe of 100∶8∶5, then transfer to a 50 mL high-pressure reactor, heat up to 200 °C at a heating rate of 30 °C / min, maintain at 200 °C for 10 h, after natural cooling, centrifuge to separate the solid and liquid, wash the solid 3 times with ultrapure water, dry the solid in an oven at 60 °C for 8 h, and finally put it into a muffle furnace and calcine at 300 °C for 4 h (in air atmosphere), and obtain the zirconium-based oxide adsorption material after natural cooling.

[0095] Comparative Example 3

[0096] A zirconium-based oxide adsorption material, the preparation method is as follows:

[0097] Under magnetic stirring, dissolve 1.5 g of ZrOCl2·8H2O solid in 20 mL of ultrapure water, then transfer to a 50 mL high-pressure reactor, heat up to 200 °C at a heating rate of 30 °C / min, maintain at 200 °C for 10 h, after natural cooling, centrifuge to separate the solid and liquid, wash the solid 3 times with ultrapure water, dry the solid in an oven at 60 °C for 8 h, and finally put it into a muffle furnace and calcine at 300 °C for 4 h (in air atmosphere), and obtain the zirconium-based oxide adsorption material after natural cooling.

[0098] The XPS pattern of the zirconium-based oxide adsorption material prepared in this comparative example is shown in Figure 2 , and the results show that the material is mainly composed of Zr element and O element. The XRD pattern is shown in Figure 3 , compared with the PDF card, this material belongs to ZrO2(00-005-0543).

[0099] Comparative Example 4

[0100] A zirconium-based oxide adsorption material, the preparation method is as follows:

[0101] Under magnetic stirring, 1.5 g of ZrOCl₂·8H₂O solid was dissolved in 20 mL of ultrapure water, Ce(NO₃)₃·6H₂O was added according to the molar ratio of Zr∶Ce of 100∶5, and then transferred to a 50 mL high-pressure reactor. The temperature was raised to 200 °C at a heating rate of 30 °C / min, maintained at 200 °C for 10 h, and after natural cooling, the solid and liquid were centrifuged. The solid was washed 3 times with ultrapure water, dried in an oven at 60 °C for 8 h, and finally calcined in a muffle furnace at 300 °C for 4 h (in an air atmosphere). After natural cooling, the zirconium-based oxide adsorption material was obtained.

[0102] Comparative Example 5

[0103] A zirconium-based oxide adsorption material, the preparation method is as follows:

[0104] Under magnetic stirring, 1.5 g of ZrOCl₂·8H₂O solid was dissolved in 20 mL of ultrapure water, Fe(NO₃)₃ was added according to the molar ratio of Zr∶Fe of 100∶12, and then transferred to a 50 mL high-pressure reactor. The temperature was raised to 200 °C at a heating rate of 30 °C / min, maintained at 200 °C for 10 h, and after natural cooling, the solid and liquid were centrifuged. The solid was washed 3 times with ultrapure water, dried in an oven at 60 °C for 8 h, and finally calcined in a muffle furnace at 300 °C for 4 h (in an air atmosphere). After natural cooling, the zirconium-based oxide adsorption material was obtained.

[0105] Application Example 1 (Determination of the removal efficiency of the zirconium-based oxide adsorption material in Example 1 for arsenic, fluorine, selenium, and chromium)

[0106] Weigh several portions of 20 mg of the zirconium-based oxide adsorption material prepared in Example 1 above, and add them successively to 40 mL of a solution with an initial arsenic, fluorine, selenium, and chromium concentration of 5 mg / L. The background solution is 0.04 mol / L sodium chloride. The pH of the solution was adjusted to 7 using sodium hydroxide solution or hydrochloric acid. After wrapping the container with aluminum foil for light shielding, it was placed on a rotary shaker. After reacting for 48 h, the solid and liquid were separated by high-speed centrifugation. The liquid was filtered through a 0.22 μm filter membrane, acidified with nitric acid, and the amounts of arsenic, selenium, and chromium in the solution were measured by inductively coupled plasma emission spectrometry (ICP-OES), and the fluorine content in the solution was measured with a fluoride ion electrode. The removal efficiency of the zirconium-based oxide for arsenic, selenium, chromium, and fluorine was calculated.

[0107] The removal efficiency of the adsorption material in Example 1 for arsenic, fluorine, selenium, and chromium is shown in Figure 5The results showed that: except for the low removal rate of Cr(III), the removal rates of F, Se(IV), Se(VI), As(III), As(V), and Cr(VI) were all higher than 95%.

[0108] Application Example 2 (Adsorption Performance of Zirconium-based Oxide on Arsenic and Fluoride)

[0109] Weigh several portions of 20 mg of the adsorbent prepared in Example 1 above, and sequentially add them to 40 mL of a solution with an initial arsenic concentration of 0 - 500 mg / L or an initial fluoride concentration of 0 - 200 mg / L. The background solution is 0.04 mol / L sodium chloride. Use sodium hydroxide solution or hydrochloric acid to adjust the pH of the solution to 7. After wrapping the container with aluminum foil for light shielding, place it on a rotary shaker. After reacting for 48 h, separate the solid and liquid by high-speed centrifugation. The liquid is filtered through a 0.22 μm filter membrane, acidified with nitric acid, and the amount of arsenic in the solution is measured by inductively coupled plasma emission spectrometry (ICP-OES), and the fluoride content in the solution is measured with a fluoride ion electrode. The maximum adsorption capacities of zirconium-based oxide for arsenic and fluoride are obtained by fitting with the Langmuir model.

[0110] Application Example 3 (Adsorption Performance of Zirconium-based Oxide on Selenium)

[0111] Weigh several portions of 20 mg of the adsorbent prepared in Example 1 above, and sequentially add them to 40 mL of a solution with an initial selenium concentration of 0 - 500 mg / L. The background solution is 0.04 mol / L sodium chloride. Use sodium hydroxide or hydrochloric acid to adjust the pH of the solution to 5. After wrapping the container with aluminum foil for light shielding, place it on a rotary shaker. After reacting for 48 h, separate the solid and liquid by high-speed centrifugation. The liquid is filtered through a 0.22 μm filter membrane, acidified with HNO3, and the amount of selenium in the solution is measured by inductively coupled plasma emission spectrometry (ICP-OES). The maximum adsorption capacity of zirconium-based oxide for selenium is obtained by fitting with the Langmuir model.

[0112] The adsorption isotherms of the zirconium-based oxide adsorbent material in Example 1 for arsenic, fluoride, and selenium and the Langmuir fitting results are shown in Figure 6 , and the data showed that: the maximum adsorption capacities of the zirconium-based oxide adsorbent material for fluoride, arsenic, and selenium are respectively: 25.5 mg F / g, 80.7 mg As(III) / g, 43.7 mg As(V) / g, 82.0 mg Se(IV) / g, 45.7 mg Se(VI) / g.

[0113] The adsorption performances of the zirconium-based oxide adsorbent materials prepared in Examples 2 - 7 and Comparative Examples 1 - 5 for various ions were determined by the methods of Application Example 3 and Application Example 4, and the results are shown in Table 1.

[0114] Table 1 Adsorption capacities (mg / g) of zirconium-based oxide adsorbents prepared in Examples 2-7 and Comparative Examples 1-5 for various ions

[0115] As(III) As(V) Se(IV) Se(VI) F Example 2 81.3 42.9 80.9 43.9 25.7 Example 3 79.6 41.6 83.6 46.1 24.6 Example 4 80.6 43.2 81.3 45.3 24.8 Example 5 81.4 42.7 83.2 44.8 25.4 Example 6 78.9 41.8 82.4 46.9 23.9 Example 7 80.7 44.1 79.8 45.5 26.1 Comparative Example 1 68.9 35.9 60.8 36.8 20.3 Comparative Example 2 67.6 37.8 67.2 34.9 20.9 Comparative Example 3 59.8 34.2 55.3 30.2 16.7 Comparative Example 4 63.6 35.1 59.6 32.1 18.1 Comparative Example 5 62.8 35.4 60.4 31.9 17.9

[0116] As can be seen from Table 1, in Comparative Examples 1 and 2, due to the adjustment of the dosage ratio of iron and cerium, the adsorption capacities of the obtained zirconium-based oxide adsorbents for the five ions all decreased. It can be seen that the ratio of iron oxide and cerium oxide in the adsorbent is very important for promoting the adsorption of pollutant ions by zirconia. In Comparative Examples 3-5, the compounding of iron and / or cerium was omitted, and the adsorption effects of the prepared adsorbents on the five ions were further reduced. Comparative Examples 1-5 fully illustrate that there is a certain synergistic effect among zirconia, iron oxide and cerium oxide.

[0117] The above are only the preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A method for preparing a zirconium-based oxide adsorption material, characterized in that, It includes the following steps: using a mixed solution of zirconium oxychloride, cerium salt and iron salt as a precursor, obtaining a precipitate through a high-pressure hydrothermal reaction, and after centrifugation, washing and calcining the precipitate to prepare the zirconium-based oxide adsorbent material; Among them, the molar ratio of the zirconium oxychloride, cerium salt and iron salt is 100∶(3 - 6)∶(8 - 12); The zirconium-based oxide adsorbent material is applied to adsorb and remove heavy metals, selenium, arsenic or fluorine pollution in groundwater, surface water or industrial wastewater; The conditions of the high-pressure hydrothermal reaction are: temperature 160 - 210 °C, time 8 - 12 h, heating rate 10 - 40 °C / min.

2. The method for preparing the zirconium-based oxide adsorbent material according to claim 1, characterized in that, The molar ratio of the zirconium oxychloride, cerium salt and iron salt is 100∶(5 - 6)∶(9 - 10).

3. The method for preparing the zirconium-based oxide adsorbent material according to claim 1, wherein The conditions of the high-pressure hydrothermal reaction are: temperature 200 °C, time 10 h, heating rate 30 °C / min.

4. The method for preparing the zirconium-based oxide adsorbent material according to claim 1, wherein, The conditions of the calcination are: first drying at 60 - 80 °C for 6 - 10 h, and then calcining at 260 - 350 °C for 3 - 6 h.

5. The method for preparing the zirconium-based oxide adsorbent material according to claim 4, wherein The calcination temperature is 300 °C and the calcination time is 4 h.

6. The preparation method of the zirconium-based oxide adsorbent material according to claim 1, wherein The atmosphere of the calcination is an air atmosphere.

7. The method for preparing the zirconium-based oxide adsorption material according to claim 1, wherein The heavy metal is cadmium.

8. A zirconium-based oxide adsorption material, characterized in that, Prepared by the preparation method according to any one of claims 1 - 7.

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